.marketing {
    height:700px;
    background:#2c343c;
    .statistic{
        
        width:45%;
        height: 30%;
        float:left;
        margin:20px;
    
    }
    .ratio {
        width:45%;
        height: 45%;
        float:right;
        margin-bottom:20px;
    }
    .rank {
        width:45%;
        height: 60%;
        float:left;
        margin-left:20px;
        margin-bottom:20px;
    }
    .flow{
        width:45%;
        height: 45%;
        float:right;
        margin-bottom:20px;
    }
}